#include "aica/aica.hpp"

extern volatile uint32_t dram[0x200000] __asm("dram");

constexpr uint32_t sectors_per_chunk = 16;
constexpr uint32_t chunk_size = 2048 * sectors_per_chunk;

__attribute__((section(".buffers.chunk")))
static uint32_t chunk[2][chunk_size / 4];

void request_chunk()
{
  constexpr uint32_t mcipd__sh4_interrupt = (1 << 5);
  aica_sound.common.mcipd = mcipd__sh4_interrupt;
}

void wait_sh4_response()
{
  constexpr uint32_t scipd__arm_interrupt = (1 << 5);
  while ((aica_sound.common.SCIPD() & scipd__arm_interrupt) == 0) {
  }
  aica_sound.common.scire = scipd__arm_interrupt;
}

extern "C"
void main()
{
  volatile uint32_t * slot = reinterpret_cast<volatile uint32_t*>(0x00800000);
  for (uint32_t i = 0; i < (sizeof (struct aica_channel)) * 64 / 4; i++) {
    slot[i] = 0;
  }

  volatile uint32_t * dsp = reinterpret_cast<volatile uint32_t*>(0x00803000);
  for (int i = 0; i < 0xb00 / 4; i++) {
    dsp[i] = 0;
  }

  aica_sound.channel[0].KYONB(1);
  aica_sound.channel[0].LPCTL(1);
  aica_sound.channel[0].PCMS(0);
  aica_sound.channel[0].LSA(0);
  aica_sound.channel[0].LEA((chunk_size / 2) * 2 - 1);
  aica_sound.channel[0].D2R(0x0);
  aica_sound.channel[0].D1R(0x0);
  aica_sound.channel[0].RR(0x1f);
  aica_sound.channel[0].AR(0x1f);

  aica_sound.channel[0].OCT(0);
  aica_sound.channel[0].FNS(0x0);
  aica_sound.channel[0].DISDL(0xf);
  aica_sound.channel[0].DIPAN(0x0);

  aica_sound.channel[0].Q(0b00100);
  aica_sound.channel[0].TL(0);
  aica_sound.channel[0].LPOFF(0);
  aica_sound.channel[0].FLV0(0x1ff8);
  aica_sound.channel[0].FLV1(0x1ff8);
  aica_sound.channel[0].FLV2(0x1ff8);
  aica_sound.channel[0].FLV3(0x1ff8);
  aica_sound.channel[0].FLV4(0x1ff8);

  aica_sound.common.mono_mem8mb_dac18b_ver_mvol =
      aica::mono_mem8mb_dac18b_ver_mvol::MONO(0)   // enable panpots
    | aica::mono_mem8mb_dac18b_ver_mvol::MEM8MB(0) // 16Mbit SDRAM
    | aica::mono_mem8mb_dac18b_ver_mvol::DAC18B(0) // 16-bit DAC
    | aica::mono_mem8mb_dac18b_ver_mvol::MVOL(0xf) // 15/15 volume
    ;

  //constexpr uint32_t tactl = 6;        // increment once every 1 samples
  //constexpr uint32_t tima = 0; // interrupt after 128 samples

  dram[0] = reinterpret_cast<uint32_t>(&chunk[0][0]);
  dram[1] = reinterpret_cast<uint32_t>(&chunk[1][0]);

  aica_sound.channel[0].SA(reinterpret_cast<const uint32_t>(&chunk[0][0]));

  int started = 0;
  while (1) {
    // detect buffer underrun

    uint32_t sample = 0;
    constexpr uint32_t samples_per_sample = 1;
    constexpr uint32_t target = chunk_size / 2 * samples_per_sample;
    constexpr uint32_t scire__sample_interval = (1 << 10);
    constexpr uint32_t scipd__sample_interval = (1 << 10);
    while (sample < target) {
      while (!(aica_sound.common.SCIPD() & scipd__sample_interval));
      aica_sound.common.scire = scire__sample_interval;
      sample++;
    }

    request_chunk();
    if (!started) {
      aica_sound.channel[0].KYONEX(1);
    }
  }
}